基于锋生函数及次级环流的早春寒潮过程分析--以宁夏回族自治区一次突发寒潮灾害性天气为例  

Analysis of Cold Wave Process in Early Spring Based on Frontogenesis Function and Secondary Circulation

作　　者：胡亮帆 王金兰 胡文东[2,3] HU Liangfan;WANG Jinlan;HU Wendong(Xinxiang Meteorological Bureau,Xinxiang 453000,Henan China;School of Atmospheric Science,Chengdu University of Information Technology,Chengdu 610225,China;Plateau Atmosphere and Environment Key Laboratory of Sichuan Province,Chengdu 610225,China)

机构地区：[1]新乡市气象局,河南新乡453000 [2]成都信息工程大学大气科学学院,成都610225 [3]高原大气与环境四川省重点实验室,成都610225

出　　处：《河南科学》2021年第9期1480-1488,共9页Henan Science

基　　金：宁夏回族自治区重点研发计划项目(2018BEG03002);成都信息工程大学启动项目(2016018);新乡市气象局自立科研项目(xx202001)。

摘　　要：利用常规观测、地面自动气象站逐时观测和ECMWF逐6 h再分析资料,从天气系统演变、冷空气的来源及路径、锋生及次级环流等方面对2016年4月2—3日宁夏一次突发寒潮极值暴雪的灾害性天气过程进行了综合分析.结果表明:①此次过程属于高空小槽东移合并型,地面有冷高压分裂且主体快速南下,并有锋面相配合,导致寒潮爆发和锋后降雪.过程前期环流形势稳定,后期天气系统突变,常规气象资料难以预报.②本次过程为对流层中下层锋生,变形项锋生、辐合项锋生起主要作用,倾斜项作用相反.③锋生函数的大值区与实况锋区的位置、演变一致,且锋生函数可定量指示锋区的强度,并通过其数值演变预报寒潮雨雪天气的出现、增强、减弱过程,可作为锋面分析过程和相关锋面天气诊断的综合物理量指标.④降水区位于急流-锋次级环流上升支的下方,与锋生函数倾斜项F4梯度大值区、上升运动极大值区均一致且峰值时刻相同.Using the conventional observation data,hourly observation data of automatic meteorological station and the ECWMF 6-hour reanalysis data,the disastrous weather process of the sudden cold wave and extreme snowstorm in 2-3 April 2016 in Ningxia was comprehensively analyzed in terms of weather system evolution,the source and path of cold air,frontogenesis and secondary circulation.The results indicate that:①This process was classified as the type of upper-air small trough moving eastward and merging.The surface cold anticyclone split and the main body moved southward rapidly with cold front,leading to the outbreak of cold wave and heavy snow after the cold front.It was difficult to predict accurately by using conventional meteorological observation data because the atmospheric circulation was stable in the early stage of the process,and the weather system changed abruptly in the later period.②This process belonged to the type of frontogenesis in the middle and lower troposphere.The deformation frontogeneis and convergence frontogenes is played the main role,while the tilt frontogenes is played an opposite role.③The large value region of the frontogenesis function was consistent with the position and evolution of actual frontal zone.The frontogenesis function could quantitatively indicate the intensity of frontal zone and predict the occurrence,enhancement and weakening process of cold wave,rain and snow through its numerical evolution,which could be used as a comprehensive physical quantity indicator for frontal analysis process and related frontal weather diagnosis.④The precipitation area was located below the ascending branch of the jet-front secondary circulation,which was consistent with the high gradient area of the frontogenesis function tilt term(F4)and the ascending movement maximum area.The precipitation,the gradient of F4 and the ascending motion reached their maximum values at the same time.

关 键 词：寒潮 锋生函数 对流层中下层锋生 次级环流 

分 类 号：P458.3[天文地球—大气科学及气象学]